1. Field
The present disclosure relates to an electronic wedge brake apparatus, in more detail, an electronic wedge brake apparatus for ensuring stable operability of an electronic wedge brake and improving durability.
2. Description of Related Art
In order to brake a front wheel of a vehicle at relatively low voltage of 12V, as shown in FIGS. 1 and 2, an electronic wedge brake apparatus using a self-servo effect has been proposed.
In this apparatus, with a fixed lower wedge 500 as a base, when a connecting spring 504 moves an upper wedge 506 along an inclined surface supported to a roller 508 by converting rotational force of a motor 502 into straight movement force, a brake disc 512 is pressed between an inner pad 510 and an outer pad 514 and rotational force of brake disc 512 is applied to upper wedge 506 to be further rotated, in which the rotational force further moves upper wedge 506 along the inclined surface supported to roller 508, such that a self-servo effect pressing brake disc 512 is generated.
When braking in the front direction, the self-servo effect is achieved by moving upper wedge 506 to the right along the inclined surface in FIG. 1, and when braking in the rear direction, the self-servo effect is achieved by moving upper wedge 506 to the left along the inclined surface. In this configuration, connecting spring 504 necessarily bends for the braking in the rear direction. As such, the connecting spring 504 needs to be flexible like a leaf spring and also stiff enough to endure the pressing force in the axial direction of motor 502.
However, as the stiffness of connecting spring 504 increases, the spring function becomes less effective. Also, if the spring is too flexible, the spring may not be stiff enough. Therefore, rear braking may be difficult or connecting spring 504 may be broken by buckling in front braking.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information constitutes prior art.